Two-Piece 16" 5.56 Mid-Length Build Kit | 12" Always Armed Octo Series M-LOK (Lightweight) | $400
Our Two-Piece Build Kit pairs a fully assembled Builder’s Grade lightweight upper with a fully assembled Andro Corp ACI-15 complete lower (no stock). Both components ship together but will not be attached in the box. If you add an optional stock, it will ship unattached and will not be installed on the lower—so you can complete final assembly your way.
- Included: (1) complete upper + (1) complete Andro Corp ACI-15 lower (no stock)
- Assembly status: Upper ships fully assembled. Lower ships fully assembled. Not attached together in the box.
- Optional stock: Ships unattached and will not be mounted on the lower.
Upper Receiver — Details
Builder's Grade Complete Lightweight 16" 5.56 Upper Receiver | Mid-Length | 12" Always Armed Octo Series M-LOK | BCG & CH
This Complete light-weight 16 inch M-LOK upper receiver comes with the Always Armed 12 inch free float Octo Series handguard and is built with only the best Mil-Spec components. The heart of this upper is comprised of a 4150 barrel and our black nitride bolt carrier group that is finished with an incredible polish, making the action smooth and easy to keep clean.
Total weight of assembled upper with BCG and charging handle is 59.3 oz ≈ 3.7 lbs
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Barrel
|
Specifications
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|---|---|
| Caliber | 5.56 |
| Length | 16" |
| Material | 4150 Chrome Moly Vanadium |
| Profile | Pencil |
| Finish | QPQ Corrosion Resistant |
| Gas System Length | MidLength |
| Gas Block Journal | .625" |
| Dimpled? | No |
| Twist Rate | 1:7 |
| Muzzle Thread | 1/2x28 TPI |
| Weight | 23.2oz |
| Barrel Extension | M4 Feed Ramps |
| Target Crown | 11 Degree |
Bolt Carrier Group:
- Enhanced 9310 Steel (Bolt)
- 8620 Tool Steel (Carrier)
- Bolt is shot Peened and MPI
- All BCG components are pre-polished before being processed and then post polished for an incredible shine
Upper Receiver:
- Slick Side - No Forward Assist / No Dust Cover
- Machined from a Mil-Spec 7075 T6 forging, Hard Coat Anodized per Mil-A-8625F, Type III
- M4 Feed ramps
- Made in the U.S.A.
Handguard:
- Free Float 12" M-Lok Hand Guard
- MIL-STD 1913 Picatinny Rail
- M-Lok Slots on 4 Sides
- 6000 Series Aluminum Extrusion
- Clamp on System for Easy Assembly
- Steel Barrel Nut & Mounting Screws Included
- Hard Coat Black Anodized Finish
- Made in the USA
- Lightweight Design
- Weight: 13.5oz
Charging Handle:
- Alloy Charging Handle Assembly
- Complete with Standard Latch
- Made from hardcoat anodized aluminum
- Black finish
Andro Corp Complete Lower — Details
The Andro Corp ACI-15 Complete Lower Receiver (No Stock) is a ready-to-build foundation for your next AR-15. Built on a 7075-T6 forged lower and finished with a MIL-SPEC lower parts kit, this complete lower includes an A2 pistol grip and a MIL-SPEC buffer tube assembly—so you can add your preferred carbine stock and hit the range. Caliber: Multi for compatibility with standard AR-15 uppers (5.56/.223, .300 BLK, etc.).
- Receiver: 7075-T6 forged, hard-use ready
- Caliber: Multi (AR-15 pattern)
- Lower Parts Kit: MIL-SPEC, installed
- Grip: A2 pistol grip
- Buffer System: MIL-SPEC buffer tube assembly installed (no stock included)
Please Note: Uppers may present light fouling from our quality control process and/or test firing
***Please allow an additional 2-3 business days of lead time as these uppers are made to order.***
Firearm Compliance & Shipping: This is a serialized firearm component and must ship to a Federal Firearms Licensee (FFL).
Before ordering, confirm your chosen FFL will complete the transfer and all required steps (background check, paperwork, fees, and any local requirements). Right To Bear does not process these steps.
All federal, state, and local laws apply. Review our policy: RTB Shipping Restrictions.
